Abstract
The exact mechanism for the production of fast
γ
-ray variability in blazars remains debated. Magnetic reconnection, in which plasmoids filled with relativistic particles and magnetic fields ...are formed, is a viable candidate to explain the broadband electromagnetic spectrum and variability of these objects. Using state-of-the-art magnetic reconnection simulations, we generate realistic
γ
-ray light curves that would be observed with the Fermi Large Area Telescope. A comparison with observed
γ
-ray flares from flat spectrum radio quasars (FSRQs) reveals that magnetic reconnection events lead to comparable flux levels and variability patterns, in particular, when the reconnection layer is slightly misaligned with the line of sight. Emission from fast plasmoids moving close to the line of sight could explain the fast variability on the timescales of minutes for which evidence has been found in observations of FSRQs. Our results motivate improvements in existing radiative transfer simulations as well as dedicated searches for fast variability as evidence for magnetic reconnection events.
Abstract
X-shaped radio galaxies (XRGs) produce misaligned X-shaped jet pairs and make up ≲10% of radio galaxies. XRGs are thought to emerge in galaxies featuring a binary supermassive black hole ...(SMBH), SMBH merger, or large-scale ambient medium asymmetry. We demonstrate that XRG morphology can naturally form without such special, preexisting conditions. Our 3D general-relativistic magnetohydrodynamic (GRMHD) simulation for the first time follows magnetized rotating gas from outside the SMBH sphere of influence of radius
R
B
to the SMBH of gravitational radius
R
g
at the largest scale separation,
R
B
/
R
g
= 10
3
, to date. Initially, our axisymmetric system of constant-density hot gas contains a weak vertical magnetic field and rotates in the equatorial plane of a rapidly spinning SMBH. We seed the gas with small-scale 2% level pressure perturbations. Infalling gas forms an accretion disk, and the SMBH launches relativistically magnetized collimated jets reaching well outside
R
B
. Under the pressure of the infalling gas, the jets intermittently turn on and off, erratically wobble, and inflate pairs of cavities in different directions, resembling an X-shaped jet morphology. Synthetic X-ray images reveal multiple pairs of jet-powered shocks and cavities. Large-scale magnetic flux accumulates on the SMBH, becomes dynamically important, and leads to a magnetically arrested disk state. The SMBH accretes at 2% of the Bondi rate (
M
̇
≃
2.4
×
10
−
3
M
⊙
yr
−
1
for M87*) and launches twin jets at
η
= 150% efficiency. These jets are powerful enough (
P
jets
≃ 2 × 10
44
erg s
−1
) to escape along the SMBH spin axis and end the short-lived intermittent jet state, whose transient nature can account for the rarity of XRGs.
Positive spillover occurs when changes in one behavior influence changes in subsequent behaviors. Evidence for such spillover and an understanding of when and how it may occur are still limited. This ...paper presents findings of a 1-year longitudinal behavior change project led by a commercial retailer in the United Kingdom and Ireland to examine behavior change and potential spillover of pro-environmental behavior, and how this may be associated with changes in environmental identity and perceptions of ease and affordability as well as perceptions of how participation in the project has helped support behavior change. We draw on both quantitative and qualitative data. Study 1 examines quantitative data from the experimental and a matched control group. Study 2 reports qualitative findings from a follow up interview study with participants of the experimental group. As expected, we found significant changes in reported pro-environmental behavior and identity in the experimental group as well as some indications of behavioral spillover. These changes were not significantly associated with changes in environmental identity. The interviews suggested that group dynamics played an important role in facilitating a sense of efficacy and promoting sustained behavior change and spillover. Moreover, the support by a trusted entity was deemed to be of crucial importance.
Film has long been defined as a temporal art, most famously by André Bazin and Andrei Tarkovsky. Yet more fundamentally it has always been a spatial art, transporting its audiences imaginatively to ...spaces and places other than those they literally inhabit. In the digital era, this spatial illusion and paradox has been greatly expanded – by the predominance of domestic film viewing, along with new extra-terrestrial perspectives, and the promise of novel kinesthetic experiences with Virtual Reality and “immersion”. The international authors in this collection address the history and aesthetics of screen media as spatial transposition, in a range of exemplary analyses that run from the landscapes of John Ford’s westerns to Chantal Akerman’s claustrophobic domestic spaces, from the conventions of the English country house film to Patrick Keiller’s Robinson roaming a changed country, and from the experiences of Covid pandemic confinement to those of un-homed van-dwellers in Chloe Zhao’s award-winning NOMADLAND.
Stories are perceived as central to modern life. Not only in narrative entertainment media, such as television, cinema, theater, but also in social media. Telling/having "a story" is widely deemed ...essential, in business as well as in social life. Does this mark an intensification of what has always been part of human cultures; or has the realm of "story" expanded to dominate twenty-first century discourse? Addressing stories is an obvious priority for the Key Debates series, and Volume 7, edited by Ian Christie and Annie van den Oever, identifies new phenomena in this field — complex narration, puzzle films, transmedia storytelling — as well as new approaches to understanding these, within narratology and bio-cultural studies. Chapters on such extended television series as Twin Peaks, Game of Thrones and Dickensian explore distinctively new forms of screen storytelling in the digital age.
With contributions by Vincent Amiel, Jan Baetens, Dominique Chateau, Ian Christie, John Ellis, Miklós Kiss, Eric de Kuyper, Sandra Laugier, Luke McKernan, José Moure, Roger Odin, Annie van den Oever, Melanie Schiller, Steven Willemsen, Robert Ziegler.
Extended criteria donor (ECD) for lung transplantation (LTx) have been implemented due to the donor organ shortage. The impact on recipient survival is under investigation. We report trends in the ...use of extended criteria lungs in the modern era and its association with survival outcomes using a large national database.
We performed a retrospective analysis of all adult LTx from May 2005 to December 2018 using the United Network for Organ Sharing database. ECD were defined by 2 or more variances from standard criteria: age ≥ 55 years, pO2 ≤ 300, pack years ≥ 20, diabetes, purulent bronchoscopy, blood infection, or abnormal chest radiographs. Transplant centers were dichotomized based on volume. Recipient survival was analyzed using lung allocation score as a covariate.
Of 24,888 LTx, 80% had extended criteria; 42% had 2 or more extensions and were deemed ECD in this analysis. Both LTx volume (2005: 1352; 2018: 2495) and use of ECD (2005: 27% ECD, 2018: 50% ECD) have increased over the study period. Survival of LTx recipients has steadily increased (2005: 82% 1-year survival in 2005; 2017: 90% 1-year survival). High-volume centers (>47 annual LTx) utilized ECD in 46% of transplants compared with 40% ECD among other centers. Recipients of ECD and standard criteria organs had no difference in 1-year survival.
Donor supply limits the number of LTx performed. Extension of donor criteria has occurred alongside increased overall LTx volume. Use of ECD did not compromise 30-day, 90-day, nor 1-year survival. Further studies are warranted to define long-term outcomes.
Watermarks reflect the very stuff of the origin, date,
distribution, composition, history, and culture of paper-based
items. Digital imaging of watermarks releases the research
potential as widely as ...the internet itself. One example is the
digital "fingerprinting" of paper in order to enhance the security
of items, such as valuable and vulnerable maps. Revealing
Watermarks offers detailed instructions of this process,
through the author's own PaperPrint method, and by means of the
case study of a sixteenth-century watermark-a crown from the arms
of Danzig-it illustrates how cultural influences spread and have
endured across the centuries, in this case from Sweden to Russia.
The late Jan Fairley (1949-2012) was a key figure in making world music a significant topic for popular music studies and an influential contributor to such world music magazines as fRoots and ...Songlines. This book celebrates her contribution to popular music scholarship by gathering her most important work together in a single place. The result is a richly informed and entertaining volume that will be of interest to all scholars in the field while also serving as an excellent introduction for students interested in popular music as a global phenomenon. Fairley's work was focused on the problems and possibilities of cross-cultural musical influences, fantasies and flows and on the importance of performing circuits and networks. Her interest in the details of music-making and in the lives of music-makers means that this collection is also an original and illuminating study of music and politics. In drawing on Jan Fairley's journalism, this volume also offers students a guide to various genres of world music, from Cuban son to flamenco, as well as an insight into the lives of such world music stars as Mercedes Sosa and Silvio RodrÃguez. This is inspiring as well as essential reading.
It is widely acknowledged that the large-scale and long-term transitions needed to mitigate climate change and to implement policies for sustainable development within planetary boundaries require ...significant shifts in values and behaviours. Consequently, there is increasing interest in the processes through which major societal transitions for sustainability can occur through peaceful cooperation and widespread embrace of pro-environmental values, and the values associated with the broad concept of sustainability such as care for the interests of future generations and concern for the poor. This encompasses the search for compelling narratives to frame the process and goals of change and the need for the fostering of virtues and ethical frameworks of identity and practice that can underpin advocacy and change for sustainability. This requires drawing on richer sources of values and ethics. We suggest that important resources can be found in religious, as well as secular traditions of social values and ethical analysis. While major religions have begun to reflect environmental concerns and sustainability goals in their theology and praxis, with immense potential and actual influence over value and behaviours, little research has explored the impacts and implications of this development; nor indeed, the intellectual stimulus and social capabilities they can offer to
secular
thinkers and practitioners in sustainable development. In particular, we argue that there is a need to consider the affinities between secular sustainability frameworks for ethics and policy and the concepts of
Catholic Social Teaching
(CST) on the
Common Good,
recently updated by Pope Francis to integrate ecological concern and a call for universal ‘ecological conversion’ and cooperation. We outline the key features of CST and the Pope’s new ‘
Integral Ecology
’ framework and identify affinities, in particular, with Elinor Ostrom’s system of design principles for sustainable management of commons. We conclude with suggestions for research to investigate the interrelationships of the Integral Ecology reframing of CST with initiatives for transformational change in values and practices for sustainability.
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